T5 HO lighting in closet

My name is Bob and I'm not only new here Im also new to growing, so any insight would be appreciated. I have an area 3'w- 7'w - 5'h. On one side I have a 48"-6 bulb-6500 fixture with 8 - 3.5 containers that I plan on letting the plants stay in thru flowering. On the other side I have a 2x2 fixture for vegging before I transplant outside. I was planning on running the lights 20 hours for a couple of weeks since I have good size clones to start with. I have a 6" hole low on an exterior wall with a fan circulating right next to it. Do I really need to cut a hole into the ceiling of the closet to let the air excape into the attic? I have a drop ceiling and opened one area for the hot air can rise into the upper 3' void (about the drop ceiling) and I can maintain a temp of about 80 degrees, with the temp under the lights @ 100 degrees... It seems if even I add and exhaust hole the temp under the light won't change that much? Is a 100 degrees to hot for the plants? Do I need to move the T5's up alittle sense Im only and 1" or 2" from the tops? Any thopughts/ideas would be cool, thanks.

100 is way to hot for the plants. Try to keep them below 80. I would hookup a 6" inline fine to the lower vent sucking cool air into the closet. And put a hole through the top to let the hot air out. You might need a fan on that one too.

I'll install one this afternoon, thanks!

KW420. I installed a ceiling fan in the drop ceiling and ran a 4" vent thru the real ceiling in the closet up into the attic. I installed it in top left side / corner since the 6" exterior vent is bottom right... The temp in the room @ floor and ceiling (6') is in the mid to low 70's... It probably has dropped the temp 10 degrees. I have a couple of other questions, first how hot should it be @ plant height under those T5's. It seems like the temp is about 100 degrees when I place a temp gauge at approx mid plant height. Right now the lights are about 2" from the top of the plants, should the lights be higher? Is there an ideal temp the plants should be @ under the lights (not room temp)? Anyways, thanks for your help and I'll install a blower if I find the circulation fan isn't working good enough located right next to the exterior vent ... Thanks again and any other members that might have some input.

100f is way hot IMHO. It helps to move the air around between the lights and the canopy. Oscillating tower fans are (tall and skinny) are perfect for this. What strain are you running? Some are more heat resistant than others. Hashberry can handle high temps pretty well in my experience. I've cooked more than my share of plants in the past with HO Flouros. :weedpoke: